Does anyone know why we exist?

There is no specific answer it's based on what you believe and trust. It all matters about how you choose to spend your life because everything now is based on reputation because we all have a mindset of surpassing certain achievements to outrank each other or for any other motive. This is mostly because of social media portraying double lives that really aren't necessary. I think as when you leave this lifetime everything such as your dramas, thoughts, actions, etc won't matter years later to anyone else unless you choose to leave a mark of your existence. Its ok if you choose not too but as I stated earlier it all depends on how you chose to act throughout your existence.

God is why we exist, sorry if this wasn't what you were looking for